90mdraid: fix/adjust 65-md* rules and related scripts

90mdraid: fix/adjust 65-md* rules and related scripts

Reworked the flow of the rules file a bit, removed redundant tests, also
should be easier to follow. It's much shorter now as well, a bit more
similar to 90lvm script - both revolve around same concepts after all.

There's no reason to treat conf-assembled arrays differently from
incremental ones. Once we hit timeout in init's udev loop, we can use
common script (mdraid_start.sh) to try force inactive arrays
into degraded mode.

md-finished.sh was kind-of out of place - it didn't really wait for any
particular device(s) to show up, just watched if onetime mdadm scripts
are still in place. Furthermore, after moving mdraid_start to --timeout
initqueue, it didn't really have too much to watch at all, besides
mdadm_auto (and that served no purpose, as we do wait for concrete
devices).

Either way, with stock 64-md fixes, current version of 65-md*.rules does
the following:

- limits assembly to certain uuids, if specified
- watch for no ddf/imsm
- if mdadm.conf => setup onetime -As script, without forced --run option
- if !mdadm.conf => incrementally assemble
- for both cases, setup timeout script, run-forcing arrays as a last resort

Signed-off-by: Michal Soltys <soltys@ziu.info>